One of the thousands of naked bike riders in Portland, June 8, 2013 (KOIN 6 News)

PORTLAND, Ore. (KOIN) — The World Naked Bike Ride is an annual event to highlight both the vulnerability of cyclists and society’s dependence on pollution-based transportation. In Portland, thousands of cyclists put their nakedness on their bike seats and rode through the streets.

The Portland ride is billed as the largest in the world and organizers hoped to break a world naked bike riding record on Saturday night.

One rider said he got the inspiration for his costume from Burning Man.

“There aren’t a lot of outfits out here, but this is a vest we made with a camp of ours from Burning Man,” Sean Hennessy told KOIN 6 News. “There’s 30 of them and they’re all synchronized together with an iPhone app. They color change, they pulse to music, they look pretty wild when you get a group of people riding together.”